My 13yr girl got her period for 1st time ever 6 days ago. it has been comin a little heavy with small clots this normal? will it get better soon?

Yes and hopefully: Yes it's normal for there to be some irregularity to the first periods. Even for a couple of years, normal to be irregular. Make sure she's at a healthy weight, as girls who are on the extreme (heavy or thin) can have more irregularity to their periods. Regular exercise, 30 minutes a day can help as well both with regulation and with some of the cramping that comes with period.